diff options
| author | Pavel Begunkov <asml.silence@gmail.com> | 2024-11-29 13:34:32 +0000 |
|---|---|---|
| committer | Jens Axboe <axboe@kernel.dk> | 2024-12-23 08:17:16 -0700 |
| commit | 087f997870a948820ec366701d178f402c6a23a3 (patch) | |
| tree | 66de9718f8265542a54a668731f2854969e3c329 /io_uring/memmap.h | |
| parent | 1e21df691ffa2c277e0b1a4928c9da0e86e9a2be (diff) | |
io_uring/memmap: implement mmap for regions
The patch implements mmap for the param region and enables the kernel
allocation mode. Internally it uses a fixed mmap offset, however the
user has to use the offset returned in
struct io_uring_region_desc::mmap_offset.
Note, mmap doesn't and can't take ->uring_lock and the region / ring
lookup is protected by ->mmap_lock, and it's directly peeking at
ctx->param_region. We can't protect io_create_region() with the
mmap_lock as it'd deadlock, which is why io_create_region_mmap_safe()
initialises it for us in a temporary variable and then publishes it
with the lock taken. It's intentionally decoupled from main region
helpers, and in the future we might want to have a list of active
regions, which then could be protected by the ->mmap_lock.
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/0f1212bd6af7fb39b63514b34fae8948014221d1.1732886067.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'io_uring/memmap.h')
| -rw-r--r-- | io_uring/memmap.h | 10 |
1 files changed, 9 insertions, 1 deletions
diff --git a/io_uring/memmap.h b/io_uring/memmap.h index 2096a8427277..2402bca3d700 100644 --- a/io_uring/memmap.h +++ b/io_uring/memmap.h @@ -1,6 +1,8 @@ #ifndef IO_URING_MEMMAP_H #define IO_URING_MEMMAP_H +#define IORING_MAP_OFF_PARAM_REGION 0x20000000ULL + struct page **io_pin_pages(unsigned long ubuf, unsigned long len, int *npages); void io_pages_free(struct page ***pages, int npages); int io_uring_mmap_pages(struct io_ring_ctx *ctx, struct vm_area_struct *vma, @@ -24,7 +26,13 @@ int io_uring_mmap(struct file *file, struct vm_area_struct *vma); void io_free_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr); int io_create_region(struct io_ring_ctx *ctx, struct io_mapped_region *mr, - struct io_uring_region_desc *reg); + struct io_uring_region_desc *reg, + unsigned long mmap_offset); + +int io_create_region_mmap_safe(struct io_ring_ctx *ctx, + struct io_mapped_region *mr, + struct io_uring_region_desc *reg, + unsigned long mmap_offset); static inline void *io_region_get_ptr(struct io_mapped_region *mr) { |